Questions tagged [can-bus]

CAN (Controller Area Network) bus (internal vehicle communications network) is a message-based protocol, designed originally for automotive applications, but can now be found in aerospace and maritime as well. This is a standard which allows different parts within a vehicle to communicate with each other without the use of a host computer.

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31
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12answers
66k views

Can a vehicle be harmed with bad inputs via an OBD-2 port?

I bought a cheap (sub $10) ELM 327 Bluetooth clone OBD-2 diagnostic adapter on a local "ebay-style" market where the seller specializes in car diagnostics and has several thousand positive reviews (...
30
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2answers
56k views

Difference between OBDII and CAN

What is CAN (controller area network)? What are the differences between an OBD-II protocol and a CAN setup?` How do I use an OBD-II scanner on a vehicle with CAN?
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3answers
5k views

Why are there multiple CAN buses in vehicles?

There are a number of questions on the CAN bus but none (so far as I can tell) that explain why there are several CAN buses in a vehicle. From what I understand many different nodes can be connected ...
16
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1answer
4k views

How do I find the correct pins in a CAN-BUS connector?

This question might be too technical for this forum, but I'll give it a go. I have a 2012 BMW R1200R motorcycle with CAN-BUS. I'd like to make an Arduino interface to the connector on the bike, but I ...
10
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2answers
4k views

Received frames from vehicles with multiple ECU chips

I'm not generally a 'car person', so hopefully I can explain this well enough to get some help here: When sending messages to an OBD-II device, I receive one response in most cars I've tested. ...
10
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2answers
1k views

Computing Wheel Torque From Engine Torque

It seems possible to obtain engine torque and RPM from a truck CAN bus. I'd like to estimate tractive force at the wheels given these two values. How should I go about computing torque at the wheels? ...
9
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4answers
14k views

Controlling door locks via CAN bus

I'm trying to figure out how to lock and unlock the doors of a 2010 Toyota RAV4 using the CAN bus via the OBD-II port. I have a microcontroller attached via an CAN controller and a CAN receiver, and I'...
9
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1answer
3k views

ATMA on OBDII not Working

I have successfully connected a terminal android app to the obd port of my car. And tried dry run of many at commands, many are working as expected. But ATMA (AT command to Monitor All) is not ...
9
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1answer
3k views

How is video transmitted in the car? (E.g., from backup camera to NAV display.)

Does video from the backup camera or side mirror camera travel to the (NAV) display via the CAN bus or some other mechanism? I'm really curious if you can get access in some way to that video - or ...
8
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1answer
6k views

Is it possible to auto close the power window of a car using OBD and CAN bus?

I am not an electrical or automobile engineer, so pardon my ignorance. I found this product in the market to auto close power windows for certain brands. How can we send signals to the CAN bus using ...
7
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1answer
3k views

Is there a way to use a PC as an ECU for testing CANBUS Sniffer devices?

Is there a way to connect CANBUS sniffer device to a PC (computer) with CAN-H and CAN-L pairs and test the sniffer device? I want to convert my PC to an ECU emulator, connect a CANBUS sniffer device'...
6
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2answers
2k views

Writing CAN Messages

I want to know what should I write with the CAN ID to send it to ECU. I am using ELM327 and Raspberry Pi with all connections to OBD-II. Initially for sending general PIDs to the ECU through ELM327 ...
6
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2answers
4k views

Is it possible to access multiple CAN buses through the OBD-II port?

As usual I apologize if this has been asked and answered somewhere. I try to only ask questions if I can't find an answer or a satisfactory answer. From my understanding the OBD-II port on vehicles ...
6
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1answer
3k views

What is the best way to reverse engineer the signals of a CAN-BUS?

There are always better ways.... I'm up to reverse engineer some CAN-BUS signals. Before I start, I'd like to discuss with guys who done this before and are willing to share their methodology. I'm ...
6
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3answers
17k views

Controlling door lock/unlock via CAN bus

I'm trying to figure out how to lock and unlock the doors of a 2016 Mercedes Citan using the CAN bus via the OBD-II port. Is there some kind of OBD-II interface where I can control this with plain ...
6
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1answer
1k views

How to control a car (accelerating, braking, steering) programmatically? [closed]

I would like to make a prototype autonomous car out of an off–the–shelf car (Toyota Yaris to be exact, but the instructions should be universal). One of the first steps is to get access to the on-...
6
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1answer
1k views

OBD2 and CAN-bus

Do all vehicles with OBD2 have a CAN-bus? Otherwise, what are the alternative buses used? Are there special versions of the buses for trucks and school-buses than for cars/suv/vans?
6
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1answer
10k views

Read steering angle data in real time

I need to read vehicle steering angle (front wheel angle) data in real time for a research project that I am involved in. How can I achieve that? What HW and SW do I need for it? So far I can think ...
5
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6answers
6k views

Since when is CAN bus mandatory for new vehicles?

The CAN bus Wikipedia page states that: CAN bus is one of five protocols used in the on-board diagnostics (OBD)-II vehicle diagnostics standard. The OBD-II standard has been mandatory for all ...
5
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1answer
619 views

About heavy-duty vehicle diagnostic port

I am trying to design an ELD device that could be connected to the deutsche 9 pin and 6 pin port on heavy-duty vehicles. Is there any place where I can get the pinout configuration of these ports for ...
5
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2answers
164 views

Can steering be electrically controlled? [closed]

Please see this: http://www.bloomberg.com/features/2015-george-hotz-self-driving-car/ George Hotz claimed he used CAN to control the car by software. I can understand that accelerating and braking ...
5
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0answers
1k views

Difference between FMS and OBD

What is the difference between FMS and OBD. Whether OBD is a standard or protocol. Recently I am working on a GPS device to tap the CAN bus in order to integrate with our fleet management system. In ...
4
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1answer
5k views

What is the difference between CAN-C and CAN-IHS buses?

When talking about a 2014 Jeep Cherokee, what is the difference between CAN-C and CAN-IHS buses?
4
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2answers
811 views

OBD or CAN - what's mandatory (EU and US)

First of all, I've already tried to do my research and tried to get all the info I'm asking for myself (which obviously didn't work). I want to know if CAN or OBD(-II) are in fact mandatory in the US ...
4
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1answer
129 views

Why modern car networks are known as “unsafe”?

Engineers and tech people like Craig Smith (who made a great book about hacking cars) never stop warning about car security. Saying that modern cars ain't secure and can be hacked from the outside (...
4
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3answers
431 views

(Mandatory in the EU) CAN through OBD-II?

I know that in the US, since 2008 vehicles must have a CAN connection on the OBD-II plug, but what about Europe? Do vehicles have to add CAN to the OBD-II plug? Or is it possible to directly send ...
4
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2answers
5k views

OBD2 CAN Protocol: ISO 15765-4

I understand that one of the CAN protocol that OBD2 uses to read vehicle data is ISO 15765-4. However this is the one that is used by generic OBD2 reader devices like ScanTool; And it provides a ...
4
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1answer
54 views

In vehicle network

There are multiple in-vehicle network types: CAN, MOST, LIN... Do vehicles typically use only one of these or do they use a combination of networks types?
3
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2answers
4k views

What happens if I shortcut the CANBUS?

It's a really simple question, but I found nothing about it on the internet. I was thinking on buying a CANBUS shield for my Arduino so that I can try to do some things on my car, but I am a bit ...
3
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1answer
4k views

OBD-II Mode and PIDs specifically used for Electric vehicles?

I am working on developing a vehicle CAN communications protocol being implemented in an electric vehicle. I was wondering if anyone knew if there is a standard MODE and PID for OBD-II messages ...
3
votes
1answer
9k views

Read vehicle speed data in real time

I need to read vehicle speed (velocity) data in real time for my research project. How can I achieve that? What HW and SW do I need for it? I guess it can be read from CAN bus via OBD2 interface? I ...
3
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2answers
2k views

How to simulate a vehicle CAN bus network?

I wish to do a project about CAN bus message testing, but without a real vehicle. Is there any way to simulate a virtual CAN bus network?
3
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1answer
81 views

CanBus - monitoring

My Volvo (2002) uses CANBus to monitor various lamps (I assume its current that's monitored). I intend to splice into one of the headlamps and one of the sidelamps and use those live feeds to dim (...
3
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1answer
2k views

CRC field calculation for CAN 2.0 B

Do you have a practical example on how to calculate the CRC field for CAN 2.0 B?
3
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0answers
581 views

CAN BUS Renault

I am in the porcess of building an application which reads live telemetry data from the inbuilt car computer and sends it to Google Firebase for analysis and informational lookup on your phone and ...
3
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0answers
2k views

BMW CAN bus data format

https://www.reddit.com/r/CANBus/comments/39pzpp/bmw_3series_2015_odometer_reading/ I am using the above website as reference and sending commands to engine ECU. I have a log from BMW engine ECU (below)...
2
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1answer
399 views

Connecting to car CANbus

I have a CANLogger 2000 and the correct supplier supplied ODB-II CANBus to 9 pin D-type cable. (http://www.csselectronics.com/screen/product/can-bus-logger-canlogger2000/language/en) The CANLogger ...
2
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2answers
1k views

Are OBD-II PID codes the same for all car manufacturers?

In the Wikipedia PID list we can see that 0x0C for engine RPM, 0x0D vehicle speed, etc. Is this same for all car manufacturers? In Arduino examples we can see that data[2] reserves the PID (for ...
2
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2answers
19k views

Citroen C4 Coupe Radio (RD4-N1) - Unlocking Aux-Input

I've recently bought this kind of device for my "Citroen C4 Coupe" with the RD4 - N1 radio (Label: Blaupunkt): Bluetooth-Transmitter Then I realised, that the radio doesn't come with a standard aux-...
2
votes
1answer
161 views

Weird OBD2 error on newer Honda models

We are using an OBD device (https://freematics.com/products/freematics-one-plus/) for some research work. We tested on several cars like Honda 2006, Subaru 2018, VW Golf 2013, Mercedes GLK 2017, etc. ...
2
votes
1answer
535 views

Scanning CANBUS [duplicate]

I am in search for a method of scanning the CAN on my car using a cheap ELM327 chip. I can query the ECU (made by Denso) without issue, however when I attempt to set the ELM327 scanner into ...
2
votes
1answer
2k views

CAN-BUS signals of Ford Transit needed

I'm looking for the specification of the CAN-BUS signals for the Ford Transit connect 2013. Does anyone know who might have done this reverse engineering already? Specifically, I'm looking for ...
2
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0answers
3k views

U0100 Toyota Aygo CAN Stop Communication or DTC Diagnostics, which is right?

I spent a lot of time trying to resolve some problems with a 2006 Toyota Aygo. The most important or significant code it has is U0100: No communication with ECM/PCM A. Information for 1KR-FE engine, ...
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2answers
2k views

Can I turn the steering wheel in Honda Civic 2017 (No Honda Sending) by sending commands via CAN bus (OBD ii port)?

I want to turn steering wheel my 2017 Honda Civic LX (without Honda Sensing) by sending commands via CAN bus (OBD ii port), My car has Electronic power steering. I am doing this because I need to some ...
1
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1answer
3k views

Sniffing the CANbus on an Audi A5

I've asked a similar question before: Connecting to car CANbus Unfortunately I haven't progressed much. The first product I tried was a CANLogger 2000, I got nowhere with it, so I sent it back. ...
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2answers
2k views

ECU signals to CAN bus

What methods or ideas are out there that can match or change an SR20det ECU's signals or codes in order for a newer CAN bus system to read, for example, the power steering to work as well as the ...
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1answer
2k views

Reading CAN messages through UART to OBD-II Board and MATLAB Toolbox

I want to read/write CAN messages. I have MATLAB in my laptop which has a Vehicle Network Toolbox which supports reading/writing CAN messages. I have my hardware OBD-II to UART board, FTDI and OBD-ii ...
1
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3answers
840 views

Are there any affordable OEM scan tool options for DIY-ers? [closed]

Every scan tool I've seen offered to consumers only provides basic OBDII or CAN data. Some only offer the ability to view basic stored codes, and maybe a freeze-frame capability. This $20 scan tool ...
1
vote
1answer
6k views

How to establish if a car has CAN Bus?

Can someone please help me on ways to establish if a car has a CAN Bus? I am specifically looking for? Physical or Technical/Electrical examination to check if its a CAN Bus I have read about ISO ...
1
vote
1answer
116 views

CAN-BUS only reading one repeating frame

I'm trying to read the CAN-BUS via the OBD port with a PiCAN, it works fine for one of our cars. But for the other (a 2007 Mini One) I'm just getting the same frame repeated until the bus is ...